Patent · US Active

Light emitting diode driving apparatus

US8536796B2 · kind B2 · utility

0Cited by

6References

15Claims

0Family size

Assignee

KONINIKLIJKE PHILIPS N.V. · NL

Inventors

Hans-Peter Loebl · Monschau, DE
Stefan Peter Grabowski · Neuss, DE

Key dates

Filing date	Oct 15, 2009
Grant date	Sep 17, 2013
Priority date	—
Expiry date	Jun 22, 2030

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02B20/30
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

A light emitting diode driving apparatus (1) comprises an arrangement (10) for supplying a signal to light emitting diodes (11, 12). The light emitting diodes (11, 12) comprise different internal impedances (41, 42) for producing different light outputs in response to a parameter of the signal having different values. As a result, the light emitting diodes (11, 12) can be driven relatively independently from each other. Each light output may have an intensity and/or a color. Different light outputs may have different intensities for dimming purposes and/or different colors for color tuning purposes. The parameter may comprise a frequency parameter and/or a timing parameter. The light emitting diodes (11, 12) may form parts of a serial branch, for example when being stacked organic light emitting diodes, or may form part of parallel branches. The internal impedances (41, 42) may comprise capacities (21, 22) and resistivities (31, 32).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.